remove coverage until JuliaLang/MbedTLS.jl#193 fixed

see: JuliaLang/MbedTLS.jl#193

Author: KDr2

.travis.yml

@@ -54,4 +54,4 @@ jobs:
     script:
     - if [[ -a .git/shallow ]]; then git fetch --unshallow; fi
     - julia -e 'using Pkg; Pkg.clone(pwd(), "Libtask"); Pkg.build("Libtask"); Pkg.test("Libtask"; coverage=true)'
-    - julia -e 'using Pkg; cd(Pkg.dir("Libtask")); Pkg.add("Coverage"); using Coverage; Coveralls.submit(process_folder())'
+    # - julia -e 'using Pkg; cd(Pkg.dir("Libtask")); Pkg.add("Coverage"); using Coverage; Coveralls.submit(process_folder())'